Expression of perivascular α-smooth muscle actin of mouse and human origin. (A) Left: Expression of mouse α-SMA was upregulated at 3 weeks in vivo compared with 1 week. However, intergroup differences were not found. Right: Expression of human α-SMA was upregulated in coculture in vitro and at both time points in vivo, although the differences were not statistically significant. (B) The expression of α-SMA was strongly downregulated for both cell/scaffold constructs at 3 weeks when compared with empty control scaffolds. ***P < 0.001; n = 6. (C) Positive staining for human α-SMA (20×) surrounding functional blood vessels was observed in both experimental groups at 3 weeks. Scale bar = 100 μm. (D) In vitro evaluation of MSCs showed positive α-SMA staining comparable to SMC (20×). Scale bar = 100 μm.